Electrical connector with low-stress, reduced-electrical-length contacts

ABSTRACT

An electrical connector adapted to receive a mating plug utilizes low-profile jack terminal contacts that can flex in their PCB-anchored base portions, which are substantially parallel to the PCB. Any bend in the distal connecting portion or in the intermediate transition portion of each terminal contact is gradual and forms an obtuse angle, thus minimizing stress concentrations. The contacts preferably are arranged in two oppositely facing and interdigitating rows of four contacts each. In one embodiment, the terminal contacts are anchored to the PCB by a contact cradle that constrains the base portion of each terminal contact at two spaced anchoring locations, allowing the base portion to flex therebetween. In another embodiment, the base portions of the terminal contacts are embedded in at least one elastomeric member, which is fitted to the PCB.

FIELD OF THE INVENTION

The invention relates to electrical connectors, such as modular jacksand plugs used in communication and data transmission systems. Examplesinclude eight-position eight-contact (8P8C) modular jacks commonly usedas Ethernet connectors.

BACKGROUND OF THE INVENTION

Near-end crosstalk (NEXT) in communication and data system connectors isan objectionable noise that results from capacitive and/or inductivecoupling among the exposed, closely spaced, parallel conductors(contacts) within the jack and/or the mating plug. Crosstalk in acommunication or data transmission system degrades the noise margin ofthe system, resulting in greater error rates in the informationconveyed. Typical solutions for reducing near-end crosstalk applycrosstalk compensation signals to the affected jack conductors atparticular locations. See, e.g., U.S. Pat. Nos. 5,997,358; 6,350,158;7,153,168; and 7,367,849, and U.S. patent application Ser. No.12/314,613, filed Dec. 12, 2008, all of which are incorporated byreference herein in their entireties.

The electrical length of a jack conductor—i.e., the distance between itspoint of contact with the inserted plug conductor and the point wherecompensation is applied—is a factor that affects the amount ofcompensation required. A shorter electrical length translates into moreeffective compensation up to higher frequencies, requiring lesscrosstalk compensation. The desired electrical length is less than 0.100in., preferably closer to 0.060 in. However, the constraints of materialand conventional jack geometry have kept the minimum electrical lengthachievable with traditional spring contact arrangements to greater than0.130 in. In such arrangements, the jack spring contacts typicallyproject away from the jack's printed circuit board (PCB) at a steepangle, resulting in high stress concentrations at each contact's rigidproximal anchoring point when deflected by an inserted connector plug.Any contact arrangement that would further shorten the electrical lengthmust achieve the desired normal contact forces throughout the requiredcontact deflection range without yielding or breaking due to excessivelocalized stresses. Solutions that attempt to achieve shorter electricallength involve rather complex arrangements, such as a movable secondPCB, e.g., as disclosed in U.S. Pat. No. 7,153,168, or unusually longcontacts that engage forward compensation contacts (see U.S. Pat. No.6,350,158).

Crosstalk amplitude generally increases with higher data transmissionrates. Network connectors attached to balanced twisted-pair coppercabling are now expected to meet at least Category 6A performancestandards, which require crosstalk levels to be at least 34 dB below thelevel of the incoming signal at 500 MHz (ANSI/TIA-568-C.2). Demands foreven higher data transmission rates are rendering some prior artsolutions unsuitable for use in modern networks. A need thus hasdeveloped for a low-noise, simple and dependable connector for use inmodern communications and data transmission systems.

SUMMARY OF THE INVENTION

The invention utilizes low-profile jack contacts that can flex in theirbase portions, which are substantially parallel to the PCB. Thus, anelectrical connector according to the invention comprises a housinghaving a plurality of walls and a plug-receiving cavity opening on afront side of the housing. A circuit board in the housing has conductivepaths, a plurality of compensation coupling contacts, and one or morecompensation elements associated with the compensation couplingcontacts. A plurality of resilient, elongated terminal contacts aresupported by and extend above the circuit board for making electricalconnections with respective wire terminals of an inserted matingconnector plug. Each of the elongated terminal contacts is associatedwith a respective compensation coupling contact and comprises a baseportion, a connecting portion and a transition portion interconnectingthe base portion and the connecting portion. A majority of the length ofthe base portion is disposed substantially parallel to the circuit boardand is supported thereby for flexural movement. The connecting portion,which makes electrical contact with the respective wire terminal of aninserted connector plug, extends obliquely above the circuit board andhas a free end. The transition portion is adapted to make electricalcontact with its respective compensation coupling contact, which servesas a fulcrum about which the connecting portion pivots when displaced bythe respective wire terminal of an inserted connector plug.

Preferably, any bend in the transition portion or in the connectingportion of each terminal contact is gradual and forms an obtuse angle,thus minimizing stress concentrations. It is also preferred that thetransition portion be wider than the connecting portion and the baseportion, both of which preferably taper substantially continuously fromthe transition portion outward. The electrical connector can beconfigured with any number of terminal contacts arranged in variousways. For example, when the connector is configured with eight terminalcontacts, the contacts preferably are arranged in two oppositely facingand interdigitating rows of four contacts each.

In one embodiment, the base portion of each terminal contact isconstrained at two spaced constraining locations and is able to flextherebetween. One of the constraining locations preferably is at thecompensation coupling contact. Constraint of the terminal contactpreferably is effected by a contact cradle above the base portions ofthe terminal contacts and attached to the circuit board. The contactcradle has a pair of discrete constraining surfaces for each terminalcontact that engage the respective terminal contact at the constraininglocations, preferably with an opening between the constraining surfaces.The contact cradle also has an aperture for each terminal contactthrough which the respective connecting portion extends and is able tomove during plug insertion and removal.

In another embodiment, instead of constraining the base portions of theterminal contacts at discrete locations, the base portion of eachterminal contact is embedded in an elastomeric member that is fixedrelative to the circuit board. Preferably, a plurality of terminalcontacts are embedded in a common elastomeric member that is fixedrelative to the circuit board. It is further preferable to have aplurality of terminal contacts embedded in one common elastomeric memberthat is fixed relative to the circuit board, and an equal number ofterminal contacts embedded another common elastomeric member that isfixed relative to the circuit board. Preferably, the elastomeric memberslie substantially in the plane of the circuit board.

A method according to the invention relates to the manner of making theelectrical connector of the second embodiment. The method comprises thesteps of embedding base portions of a plurality of elongated, resilientterminal contacts in an elastomeric member, leaving free ends of theterminal contacts exposed; fitting the elastomeric member to a circuitboard; and installing the circuit board in a connector housing. Theembedding step preferably involves arranging the base portions of theterminal contacts parallel to each other. The step of fitting theelastomeric member to the circuit board preferably involves fitting theelastomeric member so that it lies substantially in the plane of thecircuit board. Where two sets of terminal contacts are to be separatelysupported, each set is embedded in a separate elastomeric member, andthe two elastomeric members are fitted to the circuit board so that thebase portions of all of the terminal contacts are parallel, and the baseportions of one set of terminal contacts extend away from the baseportions of the other set of terminal contacts, with the free ends oftwo sets of terminal contacts interdigitating.

BRIEF DESCRIPTION OF THE DRAWINGS

Preferred embodiments of the disclosed invention, including the bestmode for carrying out the invention, are described in detail below,purely by way of example, with reference to the accompanying drawing, inwhich:

FIG. 1 is a front perspective view of a jack incorporating a PCB andcontact assembly according to a first embodiment of the invention;

FIG. 2 is a side elevational view in longitudinal cross-section of thejack of FIG. 1, with one part omitted to reveal some features hidden inFIG. 1;

FIG. 3 is a front perspective view of the jack PCB and contact assemblyof the first embodiment;

FIG. 4 is an exploded perspective view of the assembly of FIG. 3;

FIG. 5 is a side elevational view in longitudinal cross-section of theassembly of FIG. 3;

FIG. 6 is a perspective view of a resilient terminal contact used in theassembly of FIG. 3, showing relative stress levels during deflection;

FIG. 7 is a top plan view of a resilient terminal contact used in theassembly of FIG. 3;

FIG. 8 is a partial front perspective view of a jack PCB and contactassembly according to a second embodiment of the invention;

FIG. 9 is a front perspective view similar to FIG. 8, with one partomitted to reveal some features hidden in FIG. 8; and

FIG. 10 is a side elevational view in longitudinal cross-section of theassembly of FIG. 8.

DETAILED DESCRIPTION OF THE INVENTION

As used in this application, terms such as “front,” “rear,” “side,”“top,” “bottom,” “above,” “below,” “upwardly” and “downwardly” areintended to facilitate the description of the electrical receptacle ofthe invention, and are not intended to limit the structure of theinvention to any particular position or orientation.

FIGS. 1 and 2 depict a jack that incorporates a first embodiment of aPCB and contact assembly according to the invention. The jack comprisesa dielectric housing 10 similar to that disclosed in U.S. Pat. No.6,994,594, which is incorporated herein by reference in its entirety.The housing has side walls 12, a top wall 14, a rear wall 15, anextended bottom wall 16 and a front-opening plug-receiving cavity 18. Awiring unit 20 is coupled to the housing 10 and includes a printedcircuit board (PCB) 22 supported on bottom wall 16, with its narrowerfront portion 23 extending through an opening in rear wall 15 into thejack interior below cavity 18. Eight wire terminals 24 are mounted onPBC 22 (only four are visible in FIG. 2 among posts 24 a). Wireterminals 24 are standard insulation displacement contacts (IDC) towhich standard wiring (not shown) can be connected and then securedunder a snap-on cover 25, which appears only in FIG. 1. These terminalsare electrically connected via conductive traces or paths on the PCB 22respectively to eight resilient terminal contacts 40, which are held inplace on the PCB in two offset rows of four contacts each by adielectric contact cradle 30 secured to the PCB by adhesive or othersuitable means. The preferred material for terminal contacts 40 isberyllium copper (BeCu). Other suitable high-performance alloys may alsobe used.

Referring to FIGS. 3 and 4, contact cradle 30 has a profile that matchesthe narrower front portion 23 of PCB 22, and includes a semi-cylindricalpost 32 on each side that mates with a corresponding semi-cylindricalrecess 26 on each side of PCB 22. Contact cradle 30 has eight shortopenings or apertures 34 arranged in two offset rows of four apertureseach. A terminal contact 40 extends from the circuit board through eachaperture 34, which is dimensioned to allow the terminal contact 40 tomove freely during insertion and removal of a mating plug, i.e., withouttouching the contact cradle. Contact cradle 30 also has eight longeropenings 36 arranged in two offset rows of four openings each. Theseopenings are axially aligned with respective apertures 34 and overlieportions of respective terminal contacts 40. Thus, the terminal contacts40 are arranged in two interdigitating rows of four contacts each.

Referring to FIGS. 5-7, each terminal contact 40 has a substantiallyuniform thickness and three portions: a beam-like base portion 42extending along the PCB; a connecting portion 44 extending obliquelyabove the PCB through an aperture 34 for making electrical contact withthe respective wire terminal of an inserted connector plug; and atransition portion 46 interconnecting the base portion and theconnecting portion. Connecting portion 44 is distally curved to form acrest C and an obtuse angle, terminates in a slightly downwardly turnedfree end 48, and tapers from a wider section adjacent transition portion46 toward its narrower free end 48. Transition portion 46 is gentlycurved, forming an obtuse angle where it joins connecting portion 44 andbase portion 42. Transition portion 46 also rests on a respectivecompensation coupling contact 28 of the PCB, where it is constrainedagainst upward movement by an overlying web 38 of the contact cradlebetween opening 36 and aperture 34. A majority of the length of the baseportion 42 lies substantially parallel to the PCB 22. The tail end 47 ofthe base portion is constrained by a shoulder 39 of the contact cradleat the end of opening 36. Constraining shoulder 39 can be configured topermit limited upward movement of tail end 47 during insertion of amating plug, or alternatively configured to prevent any upward movementof tail end 47. The base portion 42 makes electrical contact with arespective wire terminal 24 via the PCB conductive traces or paths in aknown manner. See FIG. 4, which schematically shows a representative PCBtrace 49 extending from one terminal contact 40. Alternatively, thetransition portion 46 can communicate electrically with a respectivewire terminal 24 via its respective compensation coupling contact 28 andan associated PCB trace 49.

Compensation coupling contact 28 serves as a fulcrum about which theconnecting portion 44 of the terminal contact pivots during connectorplug insertion and removal. Accordingly, during pivoting motion of theconnecting portion 44, the unconstrained section of the base portion 42(between web 38 and shoulder 39) flexes, thus distributing bendingstresses throughout the length of the contact and minimizing stressconcentrations. The non-uniform width of the terminal contact 40,depicted in FIG. 7, results in controlled bending and also contributesto proper distribution of bending stresses. Transition portion 46, whichis the widest and overlies fulcrum 28, flexes the least. Base portion 42tapers substantially continuously from there to its tail end 47, whichis about half the width of transition portion 46. Connecting portion 44tapers substantially continuously from transition portion 46 toward theeven narrower free end 48. Relative stress levels during deflection aredepicted in FIG. 6: Lighter shading represents higher stress; darkershading represents lower stress. This distribution of stresses allowsfor proper generation of normal contact force between the matingconductors, while reducing permanent contact set and the potential forcontact failure.

Compensation (e.g., capacitive) elements 50 on or in the PCB (only onerepresentative element 50 is schematically shown in FIG. 4) communicatewith respective compensation coupling contacts 28. The electricalconnection between the transition portion 44 and the compensationcoupling contact 28 enables the application of a crosstalk compensationsignal to the terminal contact 40 at its fulcrum point. This location isa very short distance—on the order of about 0.080 in.—from the crest Cof the connecting portion 44, where the electrical interface (point ofcontact) forms between the terminal contact 40 and the wire terminal ofa fully inserted conductor plug. Accordingly, the amount of compensationrequired to counteract objectionable crosstalk is minimized, resultingin improved electrical performance.

The embodiment of FIGS. 8-10 incorporates a somewhat different contactanchoring system to achieve substantially the same improved electricalperformance in a reliable jack connector. In this embodiment, the jackhousing 10 is the same as that illustrated in FIG. 2; the wiring unit 20includes the same wire terminals 24 mounted on a PCB; and the resilientterminal contacts are arranged in two interdigitating rows of fourcontacts each. However, the PCB 122 does not have a contact cradleattached to it. Instead, the two rows of contacts 140 are fixed relativeto the PCB by two elastomeric members 134, 136, which are fitted to thePCB (e.g., bonded) in mating openings 124, 126 substantially in theplane of the PCB. The entire length of the connecting portion 144 ofeach terminal contact is exposed above the PCB. The elastomeric members134, 136 preferably are made of neoprene (poly-chloroprene) having adurometer hardness of about 40 (Shore A). Other synthetic or naturalrubber materials would also be suitable.

As in the first embodiment, the connecting portion 144 of each terminalcontact 140 tapers toward its free end 148, is distally curved to form acrest C and an obtuse angle, and terminates in a slightly downwardlyturned free end 148. The straight base portion 142 is narrower than thetransition portion 146 and is embedded in the elastomeric member 134 (or136). The transition portion 146 makes electrical contact with arespective wire terminal 24 via its respective compensation couplingcontact 128 and an associated PCB conductive trace or path (not shown)in a known manner. The transition portion 146 of this embodiment has twogentle reverse bends forming obtuse angles. One bend overlies arespective compensation coupling contact 128 on the PCB, which alsocommunicates with a respective compensation element 150 (only onerepresentative element 150 is schematically shown in FIG. 9). Asillustrated in FIG. 10, the terminal contacts 140 in their relaxed(undeflected) state are spaced from the compensation coupling contacts128, and make an electrical connection with those contacts only when theterminal contacts deflect upon insertion of a mating plug. It is alsopossible to configure the assembly such that the terminal contacts 140always engage the compensation coupling contacts 128.

Assembly of the jack of the second embodiment involves first embeddingthe terminal contacts 140, in their proper parallel positions, in theelastomeric members 134, 136, leaving the connecting portions 144exposed. The elastomeric members are then fitted to the PCB 122 inopenings 124, 126. Fitting of the elastomeric members may involve, forexample, bonding the elastomeric members to the PCB and/or engagingmating structures (e.g., ribs and grooves) on the elastomeric membersand in the openings 124, 126. The assembled PCB is then installed in thejack housing 10.

The eight-position eight-contact (8P8C) jacks of the above twoembodiments have been chosen as examples that illustrate the principlesof the invention. It should be understood by those skilled in the artthat the invention can encompass jacks having a different number and/orarrangement of contacts, and that other changes and modifications may bemade without departing from the scope of the invention as defined by theappended claims.

1. An electrical connector, comprising: a housing having a plurality ofwalls and a plug-receiving cavity opening on a front side of thehousing; a circuit board in the housing having conductive paths, aplurality of compensation coupling contacts, and one or morecompensation elements associated with the compensation couplingcontacts; and a plurality of elongated resilient terminal contactssupported by and extending above the circuit board for making electricalconnections with respective wire terminals of a mating connector plugwhen inserted into the plug-receiving cavity, each of the terminalcontacts being associated with a respective compensation couplingcontact and including: a base portion with a majority of the lengththereof disposed substantially parallel to the circuit board andsupported thereby for flexural movement; a connecting portion extendingobliquely above the circuit board for making electrical contact with therespective wire terminal of an inserted connector plug, the connectingportion having a free end; and a transition portion joining the baseportion and the connecting portion, the transition portion makingelectrical contact with the respective compensation coupling contactserving as a fulcrum about which the connecting portion pivots whendisplaced by the respective wire terminal of an inserted connector plug.2. An electrical connector according to claim 1, wherein any bend in thetransition portion or in the connecting portion of each terminal contactis gradual and forms an obtuse angle.
 3. An electrical connectoraccording to claim 2, wherein the transition portion of each terminalcontact is wider than the connecting portion and the base portionthereof.
 4. An electrical connector according to claim 3, wherein theconnecting portion and the transition portion of each terminal contacttaper substantially continuously from the transition portion outward. 5.An electrical connector according to claim 1, wherein the transitionportion of each terminal contact is wider than the connecting portionand the base portion thereof.
 6. An electrical connector according toclaim 5, wherein the connecting portion and the transition portion ofeach terminal contact taper substantially continuously from thetransition portion outward.
 7. An electrical connector according toclaim 1, comprising eight terminal contacts arranged in two oppositelyfacing and interdigitating rows of four terminal contacts each.
 8. Anelectrical connector according to claim 1, wherein the base portion ofeach terminal contact is constrained at two spaced constraininglocations and is able to flex therebetween.
 9. An electrical connectoraccording to claim 8, wherein one of the constraining locations is atthe compensation coupling contact.
 10. An electrical connector accordingto claim 9, wherein the transition portion of each terminal contact iswider than the connecting portion and the base portion thereof.
 11. Anelectrical connector according to claim 10, wherein the connectingportion and the transition portion of each terminal contact tapersubstantially continuously from the transition portion outward.
 12. Anelectrical connector according to claim 8, wherein the base portion isunconstrained between the constraining locations.
 13. An electricalconnector according to claim 8, wherein a contact cradle is above thebase portions of the terminal contacts and is attached to the circuitboard, the contact cradle having a pair of discrete constrainingsurfaces for each terminal contact that engage the respective terminalcontact at the constraining locations.
 14. An electrical connectoraccording to claim 13, wherein the contact cradle has an opening betweeneach pair of constraining surfaces.
 15. An electrical connectoraccording to claim 13, wherein the contact cradle has an aperture foreach terminal contact through which the respective connecting portionextends and is able to move during insertion and removal of a connectorplug.
 16. An electrical connector according to claim 15, wherein thefree end of each connecting portion is disposed above the contactcradle.
 17. An electrical connector according to claim 16, wherein anybend in the transition portion or in the connecting portion of eachterminal contact is gradual and forms an obtuse angle.
 18. An electricalconnector according to claim 17, comprising eight terminal contactsarranged in two oppositely facing and interdigitating rows of fourterminal contacts each.
 19. An electrical connector according to claim1, wherein the base portion of each terminal contact is embedded in anelastomeric member that is fixed relative to the circuit board.
 20. Anelectrical connector according to claim 19, wherein the transitionportion of each terminal contact is wider than the connecting portionand the base portion thereof.
 21. An electrical connector according toclaim 19, wherein a plurality of terminal contacts are embedded in acommon elastomeric member that is fixed relative to the circuit board.22. An electrical connector according to claim 21, wherein a pluralityof terminal contacts are embedded in one common elastomeric member thatis fixed relative to the circuit board, and an equal number of terminalcontacts are embedded in another common elastomeric member that is fixedrelative to the circuit board.
 23. An electrical connector according toclaim 22, wherein the elastomeric members lie substantially in a planeof the circuit board.
 24. An electrical connector according to claim 23,wherein any bend in the transition portion or in the connecting portionof each terminal contact is gradual and forms an obtuse angle.
 25. Anelectrical connector according to claim 24, comprising eight terminalcontacts arranged in two oppositely facing and interdigitating rows offour terminal contacts each.
 26. A method of making the electricalconnector of claim 1, comprising the steps of: embedding the baseportion of each terminal contact in an elastomeric member, leaving thefree ends of the terminal contacts exposed; fitting the elastomericmember to the circuit board; and installing the circuit board in thehousing.
 27. A method according to claim 26, wherein the step ofembedding comprises arranging the base portions of the terminal contactsparallel to each other.
 28. A method according to claim 27, wherein thestep of fitting the elastomeric member to the circuit board comprisessecuring the elastomeric member so that it lies substantially in theplane of the circuit board.
 29. A method according to claim 26, wherein:the step of embedding comprises separately embedding the base portionsof two separate sets of terminal contacts, equal in number, inrespective elastomeric members; and the step of fitting the elastomericmember to the circuit board comprises fitting the two elastomericmembers so that the base portions of all of the terminal contacts areparallel, and the base portions of one set of terminal contacts extendaway from the base portions of the other set of terminal contacts withthe free ends of two sets of terminal contacts interdigitating.
 30. Anelectrical connector, comprising: a housing having a plurality of wallsand a plug-receiving cavity opening on a front side of the housing; acircuit board in the housing having conductive paths, eight compensationcoupling contacts, and one or more compensation elements associated withthe compensation coupling contacts; eight elongated resilient terminalcontacts supported by and extending above the circuit board for makingelectrical connections with respective wire terminals of a matingconnector plug when inserted into the plug-receiving cavity, theterminal contacts being arranged in two oppositely facing andinterdigitating rows of four terminal contacts each, each of theterminal contacts being associated with a respective compensationcoupling contact and including: a base portion with a majority of thelength thereof disposed substantially parallel to the circuit board andsupported thereby for flexural movement; a connecting portion extendingobliquely above the circuit board for making electrical contact with therespective wire terminal of an inserted connector plug, the connectingportion having a free end; and a transition portion joining the baseportion and the connecting portion and in electrical contact with therespective compensation coupling contact, which serves as a fulcrumabout which the connecting portion pivots when displaced by therespective wire terminal of an inserted connector plug, wherein any bendin the transition portion or in the connecting portion is gradual andforms an obtuse angle; and a contact cradle attached to the circuitboard and including: eight pairs of discrete constraining surfaces, eachpair disposed above and contacting the base portion of a respectiveterminal contact, one constraining surface of each pair constraining therespective base portion against the respective compensation couplingcontact, and the other constraining surface of each pair constraining atail end of the base portion, the base portion of each terminal contactbeing unconstrained and allowed to flex between the two constrainingsurfaces; and eight apertures, one for each terminal contact, throughwhich the connecting portions of the terminal contacts extend with theirfree ends disposed above the contact cradle, and in which the connectingportions are able to move during insertion and removal of a connectorplug.
 31. An electrical connector according to claim 26, wherein thetransition portion of each terminal contact is wider than the connectingportion and the base portion thereof, and the connecting portion and thetransition portion taper substantially continuously from the transitionportion outward.
 32. An electrical connector, comprising: a housinghaving a plurality of walls and a plug-receiving cavity opening on afront side of the housing; a circuit board in the housing havingconductive paths, eight compensation coupling contacts, one or morecompensation elements associated with the compensation couplingcontacts, and a pair of spaced elastomeric members substantially in aplane of the circuit board; eight elongated resilient terminal contactssupported by the elastomeric members and extending above the circuitboard for making electrical connections with respective wire terminalsof a mating connector plug when inserted into the plug-receiving cavity,the terminal contacts being arranged in two oppositely facing andinterdigitating rows of four terminal contacts each, each row ofterminal contacts being supported by a respective elastomeric member,and each of the terminal contacts being associated with a respectivecompensation coupling contact and including: a base portion embedded inits respective elastomeric member and able to flex therein, a majorityof the length of the base portion being disposed substantially parallelto the circuit board; a connecting portion extending obliquely above thecircuit board for making electrical contact with the respective wireterminal of an inserted connector plug, the connecting portion having afree end; and a transition portion joining the base portion and theconnecting portion and disposed above its respective compensationcoupling contact, which electrically contacts the connecting portion andserves as a fulcrum about which the connecting portion pivots whendisplaced by the respective wire terminal of an inserted connector plug,wherein any bend in the transition portion or in the connecting portionis gradual and forms an obtuse angle.
 33. An electrical connectoraccording to claim 28, wherein the transition portion of each terminalcontact is wider than the connecting portion and the base portionthereof.